Field of the Invention
The present invention relates to an image forming apparatus, and more particularly relates to an image forming apparatus that includes a fan which has a pipe portion serving as an inlet/outlet gas path and a duct to which a plurality of pipe members are connected.
Description of the Related Art
In an electrophotographic image forming apparatus such as a copying machine, a facsimile machine or a printer regardless of whether it is a color type or a monochrome type, a toner is supplied from a development device to an electrostatic latent image on a photosensitive member, development is performed, a toner image developed is transferred to a sheet or the like and thereafter the toner image is heated and pressurized with a fixing device and is thereby fused and fixed to the sheet.
In recent years, even such an image forming apparatus has been required to have excellent environmental performance for realizing a comfortable office environment. Although a filter for capturing floating substances produced within an apparatus is conventionally provided, various discharge regulations are strictly prescribed by international standards due to a keen interest in the environmental performance, with the result that it is difficult to cope with such conditions with the conventional filter performance. In particular, in Europe and the like, it is required to rapidly cope with the effective removal of VOCs (Volatile Organic Compounds), UFPs (Ultrafine Particles) and the like such as toluene, styrene and siloxane substances produced from a pressure roller and the like used in the fixing device.
Japanese Unexamined Patent Application Publication No. 2006-208842 proposes a technology which blocks, with a seal plate, a gap between a fan and a duct to prevent an exhaust leakage. Japanese Unexamined Patent Application Publication No. 7-92862 proposes an exhaust device which elastically holds an ozone filter within a duct by the elasticity of a seal member.
However, the gap cannot be completely removed by the blocking of the gap with the seal plate disclosed in Japanese Unexamined Patent Application Publication No. 2006-208842, ultrafine particles such as UFPs leak, and thus it may be impossible to achieve excellent environmental performance. In the exhaust device disclosed in Japanese Unexamined Patent Application Publication No. 7-92862, since the seal member is adhered to the outer circumference of the ozone filter, for example, as shown in FIG. 8A, a minute gap may be produced in the joint of both end portions of the seal member such by variations in the dimensional accuracy of the seal member and the adherence thereof. Moreover, as shown in FIG. 8B, one end portion of the seal member overlaps the other end portion to form a laminate portion, and thus variations in the elastic deformation of the seal member are produced when the pipe member is connected, with the result that the hermeticity of a connection portion may be lowered.
The present invention is made in view of the conventional problem described above, and an object thereof is to provide an image forming apparatus which reliably prevents an air leakage from a connection portion in a fan and a duct without being affected by variations in the dimensional accuracy of the seal member and the adherence thereof and which can efficiently transport air to a filter or the like.